Experts specialize in a wide range of fields: medicine, noise pollution, car accidents, construction, etc...

Judges may call upon experts on lists.

Disputing parties can also contact these experts directly.

There is a national list of experts by specialty, drawn up by the Court of Cassation, and a list specific to each Court of Appeal, in criminal and civil matters.

Parties to a dispute may also choose an expert who is not listed by the Court of Cassation and the courts of appeal (e.g. their personal doctor). If the expert is not on a list, he or she will have to take an oath before the judge at the time of his or her hearing.

The judge is not obliged to share the expert's findings or follow his conclusions, even if he is an expert on a list. The judge remains free to decide.

The remuneration of experts shall be included in the cost of the trial.

In a civil trial, this cost may be borne by one of the parties, usually the party who lost the trial. This cost may be covered by legal aid if the losing party qualifies for it.

In a criminal trial, that cost is borne by the state.

The expert shall be supervised by the following authorities:

• First President and Chief Prosecutor of the Court of Appeal, for experts on the lists of appeal courts
• First president and general prosecutor at the Court of Cassation, for experts on the national list.

The prosecutor or the first president thus examines any breach of honor and probity on the part of an expert (for example, in the case of a false report).

Parties to a trial who wish to complain about an expert should write to these judges.